Improvement in tube-rolling machines



H08 Tube-Bolling chine.v

` Patented Oct. 5,1875.

'UNITED STATES PATENT A JOHN HOSKIN, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN TUBE-ROLLING MACHINES.

Specification forming part of Letters Patent No. 168,495, dated October 5, `1875; application filed July 16,1875.

To att whom it may concern:

Be it known that I, JOHN HOSKIN, of the city and county of Philadelphia, and State of Pennsylvania, have invented a new and useful Improvement in Tube-Rolling Machines, of which the followin g is a specification:

My invention relates to that class of tube rolling or finishing mills in which the bent skelp or'tube is welded or formed by passing it between suitable rolls and over a mandrel. In ordinary' machines of 'this class the mandrel is held stationary, and it has been found in practice that a mandrel thus held becomes cut and abraded, and too small to perform its duty properly, except in making shorter lengths of tubes than is desirable for commercial purposes.

'.Ihe object of my invention is to obviate this evil by the movement of the mandrel to a limited extent within the tube during the rolling of the same, so that new unworn portions of the mandrel may be submitted to the action of the rolls, and take t'hvfplace of the worn and cut portions. By thisiimprovement I am enabled to make longer and better tubes than. heretofore, because the working portions of the mandrel are being constantly renewed.

In the accompanying drawing, Figure 1 is a sidel view of sufficient of a tube-rolling or tube-finishing machine to illustrate my invention; Fig. 2, a side view, partly in section; and Fig. 3, a plan view.

A and Al are tube-welding rolls of the usual construction 5 B, the frame in which the rolls are caused to revolve in the direction of the arrows. G is the mandrel, made somewhat longer than usual, and adapted to the end of the shank D, the outer end of which passes through and is laterally guided by a projection, E, on the block F, the latter being rmly secured to a suitable foundation. Gr is a headed pin passing freely through and guided by a transverse hole in the arm H, which is hinged by a pin, h, to a lug on the block F. I is an eccentric lever, the fulcrumpin of which is carried by projections on the arm H, the said lever having a cam-like edge for controlling the longitudinal position of the pin Gr, and, consequently,4 that of the shank D and mandrel C, the said shank being supported near the rolls by a hinged prop, K. L represents part of a tube in position to pass onto the mandrel and between the rolls A A.

the rolls to move the mandrel and shank rear! ward to an extent and at a speed commensurate with the movement of the said eccentric lever.

Preferably the limited movement of the mandrel inside the tube, and of the tube itself, should be commenced'and 'completed in the same period of time. It will be seen that the mot-ion thus given to the mandrel will constantly carry its new and unworn parts into action between the rolls, and, consequently, the evil effects of a mandrel abraded by remaining stationary during the rolling of the tubewill be obviated.

`1t will be evident that the gradual presentation of newunabraded portions of the mandrel to the action of the rolls may be accomplisbed by moving the mandrel forward during the rolling of the tube instead of rearward, and that different devices may be'used for imparting the desired movement to the mandrel within the tube. I therefore do not restrict myself to the mechanism shown for this purpose, nor to the character of the movement ofthe mandrel, providing its unworn surface is presented to the action of the rolls as the tube passes between them; but, therefore,

I claim as my invention- The combination, in a tube-rollin g machine,

of the mandrel C with mechanism whereby' motion is imparted to the said mandrel within thetube during the pushing of the lattery over the mandrel by the rolls, as set forth.

JOHN HOSKIN.

Witnesses EDWARD H. ZITZMAN, WM. SHEARER.'

Finca 

